Molder s flask



United States Patent slgnments, to Hines Flask Company, Cleveiand, Ohio,a corporation of Ohio Application April 9, 1951, Serial No. 219,953 1Claim. (Cl. 22--11t!) This invention relates to molders flasks andparticularly to an improved means for establishing and maintainingalignment between the two elements of the flask, commonly called thedrag and cope. The invention is of that type where one member of thecomplete flask carries split pins adapted to slidably engage a recess onthe other member to maintain a snug engagement and insure the cope beingreturned accurately to position after it has been removed for theremoval of the pattern from the sand. Such split pins avoid thedifliculty with a solid pin which is either too tight in the opening inthe cope to allow it to be readily put in place or removed, or itbecomes too loose, preventing accurate replacement of the cope, and suchaccurate replacement is especially necessary in precision casting, whereit is desired to avoid subsequent machining of the article cast.

However, a difliculty has developed with such split pins that soinfrequently the cope adheres so tightly to the pin carried by the dragthat it requires jerking to loosen it, and such action is liable todisturb some of the sand. This invention provides means whereby thesplit pin may maintain its snug fit to hold the flask members inaccurate registration and still may allow the smooth and easy separationwithout danger of dislocating the sand.

To the above end, I have provided a split pin carried by one member ofthe complete mold and extending through an opening in the other memberand having a spreading tendency to cause a snug engagement therewith atall times, and I provide the pin with means limiting the spreading sothat there is no danger of the pin so adhering to such other member thatit is necessary to apply a jerk to separate the flask. The pin and itsrestraining means by which I accomplish the result is illustrated in thedrawing hereof and hereinafter more fully explained and its features aredefinitely set out in the claims.

In the drawings, Fig. 1 is a plan of a flask employing my split pinconstruction, the corner clamps being omitted for simplicity; Fig. 2 isa vertical longitudinal section of the flask in an offset planeindicated by the line 22 on Fig. 1; Fig. 3 is a fragmentary elevation ofmy invention wherein the lower member of the flask is merely a plateadapted to carry the pattern; Fig. 4 is a perspective of a ring forlimiting the spread of the split pin; Fig. 5 is a perspective of theupper portion of the split pin with the limiting ring mounted thereon.

As shown in Figs. 1 and 2, indicates the drag and 11. the cope of myflask. In Fig. 3 the drag is replaced by a flat plate 10a which maycarry the pattern and the cope 11a is the full depth of the mold. Ineither case the i lower member of the flask carries my split pin 20, asby the drag arms 12 in Fig. 2 or a projecting portion of the patternplate 10a in Fig. 3. The split pin 20 is adapted to extend through abushing 30 carried by an arm 13 extending from the cope.

The split pin 20 is tapered at its upper end inwardly Patented Jan. 31,1956 and upwardly, as shown at 21. In formed an annular groove which isoccupied by a ring 25 which is split, as shown in Fig. 4. The slot inthe split pin extends from the free end thereof nearly to the bottom andthe arms of the pin are given a tendency to spread, the spreading beinglimited by the embracing ring 25. The external diameter of this ring isless than the diameter of the bodyportion of the split pin.

With the construction described, the pin maintains a snug engagementwith the bushing 30. However, in removing the cope if there is anytendency to adhere to the this tapered portion is pm no erking action isnecessary as the pin simply collapses slightly on an upward movement ofthe cope. Such collapsing action is not suflicient to release the ring25 from the groove in the pin; it does, however, allow the cope to bereadily moved off of the pin. As soon as the cope has been removed thespreading tendency of the split pin takes up the slack between the upperend of the pin and the ring and returns the pin to normal condition.

It will be seen that my split pin with the outward tendency of its armsrestrained by the ring continuously provides means for accuratelypositioning the cope while allowing its ready placement and removal.

I claim:

In a molding apparatus, the combination of a mating pair of separableflask members adapted to be aligned in accurate registered relation witheach other, one of said members having a receiving aperture along theaxis of alignment, a pin carried at one end by the second member andextending in a direction parallel to the axis of alignment and throughthe receiving aperture for holding the members in accurate registeredalignment with each other, said pin having a progressively increasingcross sectional area from said one end throughout the major portion ofits length and tapering inwardly at the other end to a lesser crosssection, said pin also having means for reducing the enlargedcross-sectional area by permitting the pin to the resiliently squeezedtogether for insertion into the receiving aperture, said meansconsisting of the axial portion of said pin having an open slitextending along its longitudinal axis from the inwardly tapered endthroughout the major portion of its length and terminating short of saidone end to form an integral base portion having a pair of outwardlydiverging finger portions with inwardly tapered extremities, said fingerportions being resiliently yieldable toward each other about atransverse axis through the split portion of a pin, the inwardly taperedsurface of said other end of the pin being provided with acircumferential groove spaced from the pin extremity, and a ringoccupying said groove to limit the spreading of the split end of thepin, the external diameter of said ring being less than the diameter ofthe integral base portion of said pin.

References Cited in the file of this patent UNITED STATES PATENTS 92,488Strain July 13, 1869 113,313 Lipsey Apr. 4, 1871 124,071 Lipsey Feb. 27,1872 956,621 Bogenschutz May 3, 1910 1,556,368 Sperry Oct. 6, 19251,611,161 Clerke Dec. 21, 1926 2,540,237 Bevin Feb. 6, 1951 2,641,033Hines et al June 9, 1953 FOREIGN PATENTS 5,799 Great Britain of 1912663,837 France Apr. 15, 1928 466.392 Germany Oct. 5. 1928 528,173Germany June 26, 1931

